This type of device is known in principle; it has even existed for many years in a large number of devices enabling a watch bracelet to be detachably fixed onto a wrist watch. However, most of these devices are too difficult in design, require a tool to change the bracelet, risk an inadvertent detachment of the bracelet, cannot be integrated easily or on an industrial scale in existing watch cases, or have other disadvantages, such as simply being not very attractive in appearance, a characteristic that is still rather important in this field.
For example, document U.S. Pat. No. 5,914,913 discloses an interchangeable bracelet system using a pair of pins housed in two hinges positioned laterally on the watch case that can be pulled by corresponding buttons so as to be able to remove them from a corresponding housing arranged on a connection element of the end of the bracelet, this connection element being adapted to be inserted between the hinges. This system is rather difficult to integrate in most watch cases found on the market, since they require two buttons that have to be pulled towards the exterior as well as being, for the same reason, difficult to use and aesthetically unattractive.
Similar comments apply to the device proposed in European patent application EP 1 400 875. In a particular way, this device realizes a system operating in the inverse manner as compared to the device described in document U.S. Pat. No. 5,914,913, by having a pair of pins housed in a single hinge positioned laterally on the watch case, these pins being adapted to be disengaged from the interchangeable bracelet embracing this hinge and receiving the pins in corresponding housings by pushing the buttons that act on the pins inside the hinge, thus enabling disengagement of the bracelet. Being probably more suitable for use than the device described in document U.S. Pat. No. 5,914,913, this system nevertheless does not overcome the other disadvantages mentioned above and, in addition, risks being inadvertently activated by the user of the watch, since the buttons are operated by pressure instead of traction.
The Swiss patent application CH 664 663 relates to a bracelet clasp having two push buttons arranged on both sides of the clasp and each extended by a variable diameter pin, able to cooperate with two horns attached to the watch case and equipped with a slot enabling the pin to slide into the horns when the push buttons are pushed, while the pins are blocked in the tips when the push buttons are released. As with the device according to document EP 1 400 875, this system is based on the principle of two exterior buttons activated by pressure and therefore has the same overriding disadvantage, i.e. a high risk of losing the bracelet by accidentally activating the push buttons. Simultaneously, this system does not overcome the other above mentioned disadvantages and, in particular, does not improve the aesthetics since it adds an additional piece of considerable size in the form of the clasp.
Document CH 179 155 discloses two embodiments of a device to fix an interchangeable bracelet. The first embodiment uses a push button mounted vertically with respect to the plane of the watch case enabling an end of a corresponding interchangeable bracelet to be blocked or released, this end being present in the form of a large tongue of a particular shape. The second embodiment uses a locking pin mounted rotatably in the watch case and cooperating with tongues which are also of a particular shape and arranged on the end of the bracelet. Whereas the two devices proposed require specific bracelets with, in particular, the tongues of a specific shape, thus not allowing most bracelets on the market to be used, the second device proposed moreover requires the use of a tool such as a screwdriver to rotate the locking pin by 90° in order to allow the bracelet to be removed from or attached to the watch, which makes the use of such an interchangeable bracelet rather inconvenient.
Documents JP 2006/296544, U.S. Pat. No. 5,416,953, GB 2 264 628, JPH 0 174 813, and CH 73 121 disclose still other devices of this type, without the systems proposed necessarily being able to overcome all the above mentioned disadvantages. The solutions currently known from the prior art therefore cannot be considered satisfactory with respect to all aspects cited above.
Thus, a need still exists to have a device for the rapid attachment of an interchangeable watch bracelet of the above mentioned type, the design of which is relatively simple, whose operation is sure without its utilization necessarily being tedious or even requiring a tool, and which may be used with a large number of existing watch cases as well as bracelets on the market. In addition, it is desirable and important that these objectives are achieved while guaranteeing moderate production costs as well as offering an attractive aesthetic for the watches integrating this device.